7. The Menus / 7.3 Functions in the View Menu
The baseline grid are equally spaced lines covering all pages of a document. Show Lines for Baseline Grid allows to show these lines on screen.
The starting position and the distance between the lines can be set in Document Attributes dialog (see chapter 4.9). The tool settings of the text tool (see chapter 6.2.13) can be used to control whether a paragraph is aligned to the baseline grid.